viscosity

IPA/vɪˈskɒsəti/
KK[vɪskˈɑsəti]IPA/vɪˈskɑːsəti/

viscosity — noun

  • viscositysingular
  • viscositiesplural

1. how thick and sticky a liquid is, which affects how slowly or easily it pours or

1.nounB2
Definition

how thick and sticky a liquid is, which affects how slowly or easily it pours or moves

Example

The viscosity of honey makes it much harder to pour than water.

the viscosity of [liquid] + hard to pour

Lien saw the paint had higher viscosity than normal, so she added a little water.

higher viscosity + add water to reduce it

Common collocations
  • high viscosity
  • low viscosity
  • reduce the viscosity of [liquid]
  • increase the viscosity of [liquid]
Synonyms
  • thickness

    everyday word for the same idea; less precise than 'viscosity'

  • stickiness

    focuses on the adhesive quality, not resistance to flow

Antonyms
  • fluidity

    the ability of a liquid to flow easily, the opposite of high viscosity

  • thinness

    everyday opposite — a thin liquid pours fast

Grammar Patterns

the viscosity of [liquid]

Usage Note

Uncountable noun — you cannot say 'a viscosity' or 'viscosities' when referring to the general property of being thick.

Common Mistakes

The water has a high viscousity.
The water has a high viscosity.
'viscous' is the adjective form; the noun is 'viscosity'.

2. a scientific measurement of how strongly a fluid pushes back against being stirr

2.nounC1
Definition

a scientific measurement of how strongly a fluid pushes back against being stirred, poured, or forced through a narrow space

Example

Engineers measure the viscosity of crude oil before pumping it through pipelines.

measure the viscosity of [liquid] for engineering decisions

The lab report showed that the liquid's viscosity rose sharply as the temperature dropped.

viscosity rises / falls with temperature

Common collocations
  • dynamic viscosity
  • kinematic viscosity
  • measure viscosity
  • viscosity of [fluid]
  • viscosity coefficient
Synonyms
  • consistency

    broader term that includes viscosity plus other texture qualities

Grammar Patterns

the viscosity of [fluid]

measure viscosity using [apparatus]

Usage Note

In technical contexts (physics, engineering, food science) this sense is used as a measurable property with units (e.g. pascal-seconds, poise). In everyday conversation sense 1 is more common.

Common Mistakes

The viscosity of this machine is wrong.
The viscosity of this oil is wrong.
'viscosity' is a property of fluids, not machines.

Word family

Synonym discussion

Sense: noun/1

Viscosity, thickness, and stickiness all describe how a liquid behaves, but they focus on different aspects. Thickness is the everyday word for how slowly a liquid pours — honey is thick, water is thin. Stickiness adds the idea that the liquid clings to surfaces, like glue or melted sugar. Consistency is a broader term that includes thickness, smoothness, and whether a substance holds its shape. Fluidity is the opposite of viscosity — a fluid liquid pours easily. For example, 'The thickness of the milkshake made it hard to drink through a straw' uses the plain word, while 'The viscosity of the crude oil must be measured before transport' fits the formal or scientific context.

thickness ↗stickiness ↗consistency ↗fluidity ↗

Common collocations

Nouns

  • viscosity level
  • viscosity rating
  • viscosity measurement
  • viscosity index

Adverbs

  • highly viscous

Prepositions

  • viscosity of

Etymology

LatinFrenchEnglish

Viscosity comes from the Latin word 'viscosus' meaning sticky, which in turn comes from 'viscum' — the name of a sticky glue made from mistletoe berries. Ancient Romans used this glue to catch small birds. The word entered English in the 1500s, first as a medical term for bodily fluids and later as a scientific term in physics.

First known use

14th century

14th century, in the meaning defined at sense 1